What type of quantity is Avogadro's number ?

Explanation

### Step-by-Step Solution:

1. **Understanding Avogadro's Number**:
Avogadro's number, denoted as \( N_A \), is a fundamental constant in chemistry that represents the number of particles (atoms, molecules, ions, etc.) in one mole of a substance.

2. **Nature of Avogadro's Number**:
Avogadro's number quantifies the amount of substance in terms of the number of constituent particles. It is defined as:
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